alled creepy, scary and spooky, bats often get a bad rap. They’re an important species that impact our daily lives in ways we might not even realize. From pollinating our favorite fruits to eating pesky insects to inspiring medical marvels, bats are heroes of the night.
These flying mammals are incredibly unique. Even though they are common across almost the entire planet, people rarely see them because most species are nocturnal.
Fact #1: Bats are the ONLY flying mammal
Bats are the only mammals that can fly in a sustained fashion. Of course, everyone has heard of flying squirrels, but they can only GLIDE. And gliding doesn’t count as flying. Bats have cornered the market on powered mammal-flight!
Fact #2: Bats are nocturnal
Bats are creatures of the night!
If you see one during the day, that usually means there is a problem. The bat may be sick, or it’s resting place may have been disturbed by a predator. During the day, bats sleep wherever they can find a safe haven. They may roost in a cave, building, chimney, hollow tree, bat house, or even a crevice in a rocky area.
When they do come out at dusk, the first thing they usually do is head to a watering hole to get a drink of water. Next, it’s time to find food and look for insects, fruit, or blood.
Fact #3: Bats come in all different sizes
This species is only 29 to 33 mm (1.1 to 1.3 in) in length and weighs 2 g (0.071 oz)! It’s no wonder that it’s also referred to as the “bumblebee bat.” Not only is this creature the smallest bat, but it’s also one of the tiniest mammals in the world!
The largest bats are much more massive. For example, the Giant Golden-crowned Flying Fox, which is a species of fruit bat, weighs 3.1 pounds (1.4kg) and has a wingspan of roughly 5 feet!
There is almost a 700 times size difference between these two species!
Fact #4: Bats evolved independently from birds
Even though birds and bats both evolved to rule the skies, they acquired the skill of flight in entirely different ways! For example, here are some of the physiological differences between birds and bats:
Bat wings are completely unlike bird wings. Bird versions are actually “arm-bones” along the forward ridge that supports a large trailing edge composed of feathers.
Bat wings, on the other hand (no pun intended), are actual hands. They have very long fingers that go all the way from the front of the wing to the back. They are covered with a thin membrane of skin called a patagium [pah-ta-gee-um].
Bats have ridiculously over-powered hearts. They need this additional power to supply enough oxygen for flight, but their cardiovascular system is also capable of keeping the blood moving even when upside-down.
Bats have pseudo-venous-hearts. This means that when they beat their wings hard and fast, the centrifugal effect traps blood at the outer edge. They even have muscular areas out near the wingtips that can squeeze the blood back inwards so that the blood can be recirculated. Also, they have weird shunts between arteries and veins that can move blood back before it goes as far as the wingtips.
Fact #5: They “swim” through the air
Bats “swim” through the air, rather than doing the “bird flap.” In that respect, they are more like fish using propulsion through the water. This is a highly effective technique allowing bats to “flap & glide” to great effect.
Fact #6: Bats eat A LOT of bugs!
The amount of insects that bats can eat is significant. It has been estimated that some species consume upwards of 6,000 bugs in an hour! Because bats make such an excellent natural insecticide, many people try to attract them to their backyard to help control mosquitoes. In addition, most farmers love bats because of the number of insects that these flying mammals eat! Just think about it, bats are great for pest control.
Fact #7: As the bugs go, so do the bats
For bats that live in cold weather climates, they either hibernate or migrate south during the winter months. This is because there are no insects to eat! Some species choose to follow the bugs to warmer climates, while others just take a nice long nap during winter and hibernate!
Fact #8: They have a wide range of heartbeats
During hibernation, bats need so little energy that their heartbeat can drop to just four beats per minute (bpm). But when a bat is in flight, hunting, or on a long-range journey, they top out between 400 and 1,100 bpm.
Compare this range to the average human, who may have a range of 70 to 150 bpm!
Fact #9: Bats are designed to hang upside down
As you may know, bats roost and hibernate by hanging upside down!
So how do they keep all the blood from flooding their brains?
Well, bats have evolved one-way valves in their venous bloodstream to keep their heads and brains from drowning in blood. It also helps that bats have small brains, and the pressure isn’t much anyway.
Hanging upside down provides a lot of safety for bats because it makes it difficult for preying animals to reach and locate them. In addition, there is virtually no competition from other creatures for space since hanging is not a popular sleeping methodology—bats have their pick of these otherwise hard to access locations.
Fact #10: Their feet are weird
Bats have odd feet. A bat’s talons work precisely the opposite. Their claws relax into a closed position!
In fact, the tendons that close the claws are not connected to muscles at all. They tighten and close based on the fact that the body’s weight pulls them tight. Bats actually have to use muscles to open their claws, so hanging costs them absolutely no effort. Gravity does all the work for them.
Fact #11: They have a NEED for speed!
Another reason that bats roost upside down and high in the air is so that when they drop, they get enough speed to fly. Their tiny back legs won’t let them run to get ground speed for take-off, so they have to climb somewhere and drop to get started.
Bats can’t launch to fly (from the ground) because their wings don’t provide enough lift, and they cannot “leap” like a bird to get started. If they end up on the ground, they need to climb something so they can use gravity to start moving fast enough to fly successfully.
Fact #12: There are WAY more bats than you think
There are 1,300+ species of bats, which make them the SECOND most populous mammal species behind rodents.
The majority of bats are found around the equator, but they are located everywhere in the world except Antarctica. For those of us that live in Canada and the United States, we can find more than 40 different species.
Fact #13: “Blind as a bat” isn’t true
Bats can see fine, but most species use echolocation for hunting & navigation. This highly-developed system allows them to find prey, and as they get closer, they emit more and more sounds to get a precise fix.
Echolocation is the process by which animals emit calls out to their environment, and then listen to the echoes of those sounds as they bounce off nearby objects and return to them. Bats can figure out an object’s size, shape, the direction it’s moving (if any), and how far away their target is by using echolocation.
Many species of bats use echolocation, and it’s the way they can see in complete darkness!
If you have ever been outside on a warm summer night and were bitten by mosquitoes, you know how many insects come out once the sun goes down. For insect-eaters like bats, nighttime is the BEST time to be tracking down bugs. Echolocation allows bats to hunt at night when their primary food source is most plentiful, AND they don’t have to compete with other animals, such as birds.
But not all bats use echolocation
For example, fruit bats rely on their eyesight to find food. Just think about it, a guava fruit doesn’t play hopscotch across tree limbs to elude a bat. Being stuck to a branch seems to eliminate the possibility of a footrace to freedom, so bats that eat fruit don’t need echolocation to find their food.
Fact #14: Some bats really do drink blood!
Yes, some bat species drink blood, usually from cows, pigs, horses, and similar animals. Interestingly, these types of bats are appropriately called “vampire bats.”
The interesting part is that most of the time, the large animal that’s getting its blood sucked doesn’t even realize what’s happening. The teeth of these bats are so sharp you can’t feel them. The victims are completely unaware that they supplied dinner.
Only three kinds of bats are blood-only feeders:
- Common Vampire Bat
- Hairy-legged Vampire Bat
- White-winged Vampire Bat
Interestingly, these species are significant contributors to medicine, especially for humans with blood-clotting issues. The anticoagulant in their saliva has helped researchers investigate and develop drugs for arteriosclerosis (hardening of the arteries) and cardiovascular disease.
Fact #15: Some bats eat fruit or nectar
Fruit-eating bats spread seeds and maintain biodiversity in the tropics. They serve an important role in recovering parts of the jungle that have been clear-cut by humans. Bats also like to lick flowers to obtain the nectar, so some species serve as primary pollinators for certain types of plants.
Fact #16: Some bats like company, others don’t
Some bats choose to live alone, getting together only for mating purposes. But the majority of species gather together in colonies of 100+, and it’s common also to see them living together in the thousands!